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Chinese Science Bulletin 1991年第5期36卷 438-439页

作者：丁勇 Nanjing Medical College Nanjing 210029 PRC

The michaelis-Menten elimination process for intravenous injection can be described as-dC/dt= VmC/（Km+C）. （1）The equations for the maximum, minimum and average plasma concentration of drugswhich obey Eq.（1）in st... 详细信息

关键词： intravenous elimination michaelis Wagner 士一

On Single Compartment Pharmacokinetic Model Systems that Obey michaelis-Menten Kinetics and Systems that Obey Krebs Cycle Kinetics

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Journal of Encapsulation and Adsorption Sciences 2011年第3期1卷 43-50页

作者： Kal Renganathan Sharma 不详

The integration of michaelis-Menten kinetics results in a trancedental equation. The results are not in a form that is readily usable. A more usable form of the model solutions is developed. This was accomplished by using Taylor series expansion of dimensionless concentration u in terms of its derivatives. The infinite series expression for dimensionless concentration is given. It can be seen that for times t michaelis constant and the desired accuracy level needed. The single compartment model solution was obtained by the method of Laplace transform. It can be seen from Figure 2 that the dimensionless drug concentration in the compartment goes through a maxima. The curve is convex throughout the absorption and elimination processes. The drug gets completely depleted after a said time. The curve is asymmetrical with a right skew. The systems under absorption with elimination that obey the kinetics that can be represented by a set of reactions in circle were considered. A system of simple reactions in circle was taken into account. The concentration profile of the reactants were obtained by the method of Laplace transforms. The conditions when subcritical damped oscillations can be expected are derived. A model was developed for cases when absorption kinetics exhibit subcritical damped oscillations. The solution was developed by the method of Laplace transforms. The solution for dimensionless concentration of the drug in single compartment for different values of rate constants and dimensionless frequency are shown in Figures 6-9. The drug profile reaches a maximum and drops to zero concen-tration after a said time. The fluctuations in concentration depends on the dimensionless

关键词： Single Compartment Models michaelis and Menten Kinetics Reactions in Circle Subcritical Damped Oscillations Pharmacokinetics

静注michaelis-Menten消除动力学模型的简单判别法

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数理医药学杂志 1992年第2期5卷 24-26页

作者：丁勇南京医学院数学教研室南京210029

给出了根据一次静注给药后的C—t数据即可识别线性模型与michaelis—Menten消除动力学模型的三种简便方法。

关键词：判别法 michaelis 线性模型动力学模型血药浓度一室模型药物动力学研究线性动力学多室模型模型识别

米氏(michaelis—Menten)方程及赖氏(Lineweaver—Burk)方程的意义及其在生理学中的应用(讲座)

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川北医学院学报 1986年第2期 69-71页

作者：朱康民川北医学院生理学教研室

michaelis 与 Menten 二人于1913年建立了酶反应速度与底物浓度关系的等轴双曲线方程,此方程是以底物与酶形成复合物这一中间过程为基础。但必须有以下两个前提:①在反应初期底物浓度可看作与反应前浓度相等,即[S](反应初期浓度)=[S]

关键词：等轴双曲线方程底物浓度反应速度 Lineweaver Menten michaelis Burk 生理学基础医学

长时间反应条件下michaelis-Menten方程讨论

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安庆师范学院学报（自然科学版） 1994年第1期 78-80页

作者：张群

长时间反应条件下,酶促反应体系如何使用michaelis—Menten方程进行积分计算,是酶应用中常常遇到的一个问题,本文以michaelis—Menren方程赖以建立的条件为出发点,讨论了具有不同特征的酶促反应体系在长时间反应条件下,用michaelis—Men... 详细信息

长时间反应条件下,酶促反应体系如何使用michaelis—Menten方程进行积分计算,是酶应用中常常遇到的一个问题,本文以michaelis—Menren方程赖以建立的条件为出发点,讨论了具有不同特征的酶促反应体系在长时间反应条件下,用michaelis—Menten方程进行积分计算的条件。

关键词： michaelis 积分计算一个问题酶促反应积分区间动力学常数非竞争性抑制积分式速度方程初始反应

静注michaelis-Menten消除动力学稳态浓度研究

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科学通报 1990年第22期35卷 1760-1760页

作者：丁勇南京医学院基础医学部南京 210029

对每隔一定时间τ,静脉注射一个剂量D的给药方式,导出了michaelis-Menten消除动力学模型

关键词： michaelis 表观分布容积最大速率

静注michaelis—Menten消除动力学模型的简易判别法

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中国医学物理学杂志 1991年第Z1期8卷 88-88页

作者：丁勇南京医学院

michaelis—Menten消除动力学模型(简称M—M模型)在非线性药物动力学中占重要地位,在药物动力学中,线性与非线性模型的一个重要区别在于血药浓度与剂量是否成比例,用该方法进行模型识别,需要多个不同剂量的血药浓度(C)一时间(t)数据,因... 详细信息

michaelis—Menten消除动力学模型(简称M—M模型)在非线性药物动力学中占重要地位,在药物动力学中,线性与非线性模型的一个重要区别在于血药浓度与剂量是否成比例,用该方法进行模型识别,需要多个不同剂量的血药浓度(C)一时间(t)数据,因此对于应用,特别是临床应用,很不方便。在静注给药的情况下,本文证明了:

关键词：药物动力学血药浓度 Menten 模型识别判别法 michaelis 线性与非线性临床应用一室模型成比例

Purification and Characterization of Alkaline Xylanase Secreted from <i>Paenibacillus macquariensis</i>

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Advances in Microbiology 2013年第1期3卷 32-41页

作者： Meeta Sharma Saurabh Mehta Anil Kumar School of Biotechnology Devi Ahilya University Indore India

An alkaline xylanase secreted by Paenibacillus macquariensis RC 1819 has been purified using ammonium sulfate fractionation, ion exchange chromatography using DEAE-cellulose and gel filtration chromatography over Sephadex G-200 and Sephadex G-100. The purified enzyme had the specific activity, 25.2 units/mg protein with birchwood xylan as a substrate. The purified enzyme showed a single protein band over sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight of the enzyme has been found to be 31,000 ± 2000 as determined by using Sephadex G-200 gel filtration chromatography. The subunit molecular weight has also been found to be ~31,000 as determined using SDS-PAGE indicating monomeric enzyme. The enzyme showed optimum activity at pH 8.6 and temperature, 50°C. The michaelis constant (Km) of the enzyme for birchwood xylan was 2.2 mg/ml as determined using velocity saturation plot. The metal ions viz. Co+2 and Mn+2 stimulated xylanase enzyme activity whereas Hg+2 inhibited the enzyme activity.

关键词： Xylanase Paenibacillus macquariensis Purification michaelis Constant Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis

On Damped Wave Diffusion of Oxygen in Pancreatic Islets: Parabolic and Hyperbolic Models

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Journal of Encapsulation and Adsorption Sciences 2012年第3期2卷 33-41页

作者： Kal Renganathan Sharma Advanced Technology Center & Biotechnology Institute Lone Star College CYFair Cypress TX & Department of Physics Texas Southern University Houston USA

Damped wave diffusion effects during oxygen transport in islets of Langerhans is studied. Simultaneous reaction and diffusion models were developed. The asymptotic limits of first and zeroth order in michaelis and Menten kinetics was used in the study. Parabolic Fick diffusion and hyperbolic damped wave diffusion were studied separately. Method of relativistic transformation was used in order to obtain the solution for the hyperbolic model. Model solutions was used to obtain mass inertial times. Convective boundary condition was used. Sharma number (mass) may be used in evaluating the importance of the damped wave diffusion process in relation to other processes such as convection, Fick steady diffusion in the given application. Four regimes can be identified in the solution of hyperbolic damped wave diffusion model. These are;1) Zero Transfer Inertial Regime, 0 0≤τ≤τinertia;2) Rising Regime during times greater than inertial regime and less than at the wave front, Xp > τ, 3) at Wave front , τ = Xp;4) Falling Regime in open Interval, of times greater than at the wave front, τ > Xp. Method of superposition of steady state concentration and transient concentration used in both solutions of parabolic and hyperbolic models. Expression for steady state concentration developed. Closed form analytic model solutions developed in asymptotic limits of michaelis and Menten kinetic at zeroth order and first order. Expression for Penetration Length Derived-Hypoxia Explained. Expression for Inertial Lag Time Derived. Solution was obtained by the method of separation of variables for transient for parabolic model and by the method of relativistic transformation for hyperbolic models. The concentration profile was expressed as a sum of steadty state and transient parts.

关键词： C Type I Diabetes Simultaneous Reaction and Diffusion michaelis and Menten Kinetics Damped Wave Diffusion Relativistic Transformation Hyperbolic Models Parabolic Models Islets of Langerhans

KINETICS OF THE EFFECT OF INHIBITORS ON SYSTEMS INVOLVING TWO ENZYME-SUBSTRATE INTERMEDIATES

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Science China Mathematics 1964年第2期 269-277页

作者：許根俊邹承魯 Institute of Biochemistry Academia Sinica Shanghai

It has become increasingly apparent in recent years that in the mechanism of catalysis of a large number of enzymes, including hydrolases, transferases, lyases, isomerases, ligases, and oxidoreductases, two ES intermediates are involved (Scheme 2). The kinetic behaviour of such systems towards inhibitors has been studied and a general equation is obtained. An examination of the conditions required for the perturbation terms to vanish shows that besides competitive and uncompetitive interactions, if a plot of 1/v against 1/S for various concentrations of the inhibitor gives straight lines with the intersection point in the second quadrant or on the 1/S axis, then, in general, K-1,>>k+2, and at the same time, E, ES, EY, and EYS are in quasiequilibrium. Furthermore, when k+3>>k+2, the experimentally determined michaelis constant is equal to the dissociation constant of the michaelis complex, that is to say, the conclusion reached by Botts and Morales can also apply. The relationship between the michaelis constant and the dissociation constant of the michaelis complex has also been discussed for the case k+2≥k+3. On the basis of the above analysis, some of the kinetic behaviours of chymotrypsin, papain, and aldolase are discussed.

关键词： dissociation michaelis catalysis perturbation behaviour straight intersection conclusion competitive esters